Checking the input/output of a soundcard - use with an FT-450D

On the Facebook group for Ham Radio Deluxe somebody had posted a link to a video highlighting a "bug" in soundcards that use a particular Texas Instruments audio chipset - the affected chipset is the TI PCM2900 series PCM2904 and below, pre-C revisions. See here for Reddit article.

Some radios have this chipset built into them. My Yaesu FT450-D is NOT one of them fortunately.

I had a look at the YouTube video https://www.youtube.com/watch?v=guH0NMRRTAo and the poster John Sands had a lot of useful information including how to temporarily fix it if you have the chipset. There was a link to a freeware piece of software for a Peak Level Meter darwooddesigns.co.uk/pc2/meters.html and on the Facebook page of HRD somebody linked to a Soundcard Oscilloscope zeitnitz.eu/scope_en which can be used to check the waveform of your signals.

G8YPH Soundcard Usage

The PC connected to my various radios has 4 soundcards built into it:

• The internal onboard Dell soundcard is disabled in the BIOS
• A EMU-0404 PCI high spec professional soundcard - many input/outputs, ASIO, WAVE, Full MIDI, DSP configuration possible with this card - drivers up to Windows 7 64bit are only available for this now though. So Windows 8.1 and Windows 10 might not work.
• 2 x USB cheap soundcards (costing a few quid from Amazon)

The latter soundcards are the ones that I use for the Yaesu FT-450D as they are connected to a powered USB hub close by the rigs.

The only issue I had to resolve with these sound cards are that they are not shielded. I added some domestic aluminium foil around the body and loosely connected it to the ground/earth of the USB plug. This simple modification worked very well and the dongle does not pickup any stray RF at all.
A long term modification would be to replace the aluminium with self adhesive copper foil wrapped around the case with a soldered connection to the ground. However for the time being the aluminium works well.
The sound card automatically picks up the necessary drivers from Microsoft's Windows Update site and the driver it uses is:

• USB PnP Sound Device
• Driver Provider: Microsoft
• Driver Date: 12/07/2013
• Driver Version: 6.1.7601.18208
• Digital Signer: Microsoft Windows

General Tab

Driver Tab

Driver Details

The controller information field shows up my cards as being 3-USB PnP Sound Device and 5-USB PnP Sound Device (Generic USB Audio)

If you plug the device into a different USB socket it will pickup a different number.

Naming sound cards

Recording Device Naming

Playback Device Naming

It's always a good idea to name any devices you have in Windows from the defaults ones. It aids signal tracing later on.
I have named my devices as this:
3-USB PnP Sound Device - from now on known in the blog as Soundcard #3

• Recording - RX from FT-450D
• Playback - TX to FT-450D

5-USB PnP Sound Device - from now on know in the blog as Soundcard #5

• Recording - FT-450D Headphone Socket
• Playback - NOT IN USE - I don't use this currently for anything.

The 3.5mm (1/8") plugs on the custom lead coming from the Yaesu FT-450D Data socket are plugged into the relevant sockets on the 3-USB PnP Sound Device. I also have a lead coming from the headphone socket of the rig going to the recording socket of the 5-USB PnP Sound Device.

Sound Card Levels

As the input and output levels of the FT-450D data socket are fixed then you have to resort to using the digital attenuator supplied by the driver to the sound card. Fortunately the input and output of the rig are matched (impedance and line level) to the typical computer soundcard.
On Soundcard #3 I have the following for the "Recording" settings:

General Tab
This is where you change the name of the device and
change its icon

Listen Tab

NOTE AGC on the Custom Tab is disabled

Levels Tab

Advanced Tab

For the Soundcard #3 "Playback" settings I have this

General tab
I have renamed it to something meaningful

Levels tab
63% seems to work well for me
ALC is controlled from within DM780 itself
as seen in another of my blog posts

Enhancements tab
Nothing is selected here and left at default

Advanced tab
Again nothing is changed here

On Soundcard #5 I have the following settings for the "Recording" settings :

General tab
Note I have changed the Icon to a set of headphones

Listen tab
The "Listen to this device" checkbox is ticked
see further down for details

NOTE AGC on the Custom Tab is disabled

Level Tab

Advanced Tab

I don't use the playback section of the Soundcard #5 so haven't included it.

Monitoring the rig output

I have the recording input of device 5 set to playback through the default playback device - in my case the EMU-0404
To do this:
In the Sound manager open the properties of the device

• go to the Listen tab
• check the Listen to this device box
• make sure the Default Playback Device is selected
• Click OK twice.

You can then listen to the output of the the FT450D through the shack speakers and control the level using the AF Gain control on the rig (or control that with HRD Rig Control)

Monitoring sound card output

The Digital Level Meter software from darkwooddesigns.co.uk can be configured to monitor the input level of any of your sound cards.
I set mine to monitor Soundcard#3 microphone socket - this is connected to the rig data output socket. I tuned to a typical busy position of the 20m band which has a lot of activity - 14.070 MHz USB the PSK portion.
As the level of the digital attenuator is set to 49%  I get peaks of around -3.8dB and an average of -8dB which is just less that the software overload position.

A good peak level

I turned the attenuator up to 100% (so it wasn't doing anything) and immediately went into the red peaking at 0db - and flashing OVERLOAD - which I would have expected. This was also verified in the DM780 module too as everything was saying OVERLOAD

Bad peak level

As there was no way of turning down what is coming from the rig the only alternative is to activate the digital attenuator on the soundcard. This is not an ideal but the only thing I have.
I turned the attenuator back to 49% and all was well.

Using a digital oscilloscope to check the waveform for clipping.

The Soundcard Oscilloscope software can be used to check any permutation of soundcard within a PC. I had a look at the waveform of the signal on the Soundcard#3 microphone socket.

When set at 49% the signal was pure and smooth. When increased to 70% the peak level meter was just peaking into Overload also confirmed with DM780. The waveform on the Oscilloscope was also starting to clip.
I increased the level to 100% and the waveforms were continually clipping.

So I decreased the level back to 49% again and all returned to normality.

I think that level works well for me although I don't currently operate any of the JT65 or JT65-HF weak signal modes. These modes need your sound card set for optimum levels and the two pieces of software I highlighted can help in setting your station up to operate these modes.

Monitoring Sound Card Input,

It's always nice to see the signal that your PC is generating is at a good level and isn't introducing distortion into the start of the signal chain.
The Software Oscilloscope can be used to monitor the signal both coming from the computer and into the soundcard feeding the rig.

In my case I chose Loopback: TX to FT-450D
(aren;t you glad you named the soundcards earlier on!)

You can compare the waveform and make the necessary level adjustments.

A fairly smooth waveform being fed into the sound card

Conclusion

It is easy to monitor the levels and waveforms of digimode audio both going in and coming out of your rig using a few simple freeware programs. You can then make sure you are making the most of your computer by obtaining the cleanest possible audio signal.

Working SOTA stations

I have one of the rigs on S20 most of the time I'm in the shack listening for local FM contacts. Occasionally I hear operators calling CQ SOTA. I try to always reply to them as they have taken the time to climb up to the top of a high point. It must be really disappointing when nobody replies back to them so I encourage everybody who hears a CQ SOTA to please reply.

I was just speaking with Tom M1EYP stood upon SP15 "The Cloud" near Bosley, Macclesfield. He wanted other operators to also try reponding to him on 6m SSB. I of course am fully equipped for most bands and was able to just pick him out of the noise. He gave me a 59 response he was only 41 to 51.
On 2m FM he was 59 end stop.

I also send eQSL cards out too so they have proof of the 2 way contact should they need it for an activation. Tom was no exception and an eQSL is on its way.

Noisy 20m band and quiet 15m band

I normally work the 20 and 15m bands in the morning through into the late afternoon. Over the last few months this has been really lucrative being able to work many countries during the day. Over the last couple of days 20m has developed a lot of atmospheric noise and 15m has become fairly quiet.

I hope the bands will improve otherwise I'll have to go back to VHF/UHF for a while :(

Tuning out QRM on datamodes using the Yaesu FT-450D with DM-780 and Ham Radio Deluxe

The standard way of operating a datamode such as PSK-31 is to leave the filter width as wide as you can and tune to the operating frequency. The software, in my case Ham Radio Deluxe running the DM780 module, then uses software filters to narrow reception down to whatever audio frequency you have selected in the waterfall. This works well 99% of the time but you do get occasions in the middle of a QSO when a very strong station starts transmitting in an adjacent audio frequency. That station probably can't hear your contact so doesn't know that it is generating QRM.
This can sometimes result in swamping the signal coming from your contact.

The two useful filters on the FT-450D highlighted in yellow

The radio then comes to the rescue. From very early days it has been possible to engage IF filters, notch filters and such like on communications equipment. When somebody is tuning up close to your listening frequency engage your tunable notch filter. If somebody is transmitting on SSB a few KHz up then engage your IF Shift. The ways of getting rid of QRM are very wide ranging and easy to do.

Diamond V-2000 triband vertical review - a replacement for an older Diamond X-50 dual bander

My old Diamond X-50

The new Diamond V-2000 in situ
The 6m inverted V is pointing
east to Europe

Diamond X-50

As mentioned in a previous post my dual band colinear had suddenly gone deaf. When taken down it was found to be a Diamond X-50. I had totally forgotten what make or manufacturer it was. It was still in excellent condition when it was brought down from its home for the last 15 years atop an 8 foot long pole.

I investigated it and found that the PL259 had a slight amount of corrosion despite it being wrapped in self amalgamating tape and in turn being inside the lower pipe of the antenna.

Diamond V-2000 triband vertical antenna

I received the new antenna and assembled it. This one now has two set screws holding the support pipe to the base of the antenna so Diamond have listened to the criticism on internet forums about the the previous 1 set screw fixing. Now it is really strong and gives you confidence.

Yaesu FT-450D using the internal ATU at the same time as an external ATU

I have an external ATU made by LDG, The Z-100Plus Autotuner, connected to the rig with a short section of 50ohm cable (500mm long). I use this as the internal ATU inside the FT-450D will not tune my end fed dipole on any band.

Following on from a query by a local ham I need to explain I have been experimenting using the internal ATU within the Yaesu FT-450D at the same time as the external ATU and am having good results. I have the Yaesu internal ATU set to be in circuit both on transmit and receive (out of the box as a default the FT-450D is set to be in circuit just on transmit).

It must be stressed that I don't tune both ATU's at the same time.

The way I do it is tune up on the desired band and frequency using low power through the Z-100 Plus. This gets the load presented by the antenna to the rig within range. Then I press and hold the tune button on the rig and let it do its stuff too. A further tune on the Z-100 retains exactly the same settings. In other words the external ATU is still tuned so doesn't go through its tuning cycle again.

 When I take the internal ATU out of circuit while receiving a fairly stable signal I do see the S meter drop 1 or two points. I have also switched it into circuit and found that I get a noticeable improvement in reception on very weak signals.

My belief is that both ATU's compliment each other and the only thing in the manual says "Yaesu recommend keeping the ATU in circuit all the time". My view it that the internal ATU just sees a load to match to the power amplifier and doesn't know or care that there is another ATU between it and the antenna.

I am aware that there is debate whether both ATU's should be used and certain manufacturers rig operating manuals say not to do it. I only present the results that I am seeing and that is part of what amateur radio is about - experimentation. I take no responsibility for what you do in your own shack.

Avair AV-601 review

I have had an old AEC SWR-50A for the last 35 years and it has finally given up the ghost. To be quite honest it was never really good and now its adjustment potentiometer was shot. I needed another more modern VSWR/Power meter.
I opted for the Avair AV-601 as it covered frequencies from 1.8MHz up to 525MHz that covers most of the radios I have.

I ordered it from Martin Lynch on a Sunday evening and it arrived yesterday 08/07/2015 in a padded bag. I opened it and the cardboard cover for it was a little battered but the meter was inside a large padded bubble wrap sleeve and was fully protected.

Front panel

The instrument itself comprises a large metal box, solidly built and is dominated by a large multipurpose meter. There are 4 rubber feet on the bottom, it is finished in black with silk screen printed lettering. The instrument weighs 720 grams and measures 150mm wide x 50mm high x 100mm deep so should fit in a convenient location in the shack. The RF and power connections are all on the rear panel so make allowances for these connectors.

DM780 Waterfall hiccups

I noticed the other day that the waterfall was hiccuping from time to time. I thought nothing of it as "it was probably something cosmetic to do with the display driver". Oh how wrong I was.
I was in QSO with a guy on lowly PSK31 and noticed that my last 73 over to him stumbled slightly and took much longer to complete than normal.

Now my Windows 7 64 bit PC is not slow nor lacking in RAM but I investigated to find a process taking an inordinate amount of memory (almost 2GB). It was the "svchost.exe -k LocalSystemNetworkRestricted" host process. I know from my work in computers that sometimes hackers replace this file with their own.
To cure this I first of all killed the process and then ran up an administrative cmd.exe prompt (right click the cmd icon on your start menu and select run as administrator)
Then I typed in the cmd line sfc /scannow and let it run to its conclusion. This will report on whether any essential system files have been replaced with dodgy ones and repair them with the original Microsoft ones if it finds any. Fortunately it did not find any and I noticed that svchost had automatically restarted.

I monitored this over the next few days and it took no more that 220 MB of RAM - not bad for an 8GB machine.

DM780 no longer stutters. So have a look at your machine before you blame the HRD software!

For more information about sfc have a look at Microsoft Knowledgebase article here